Welsh Harlequin Sexing Feedback

My first test batch of Welsh Harlequin eggs hatched last night, and I was hoping for some assistance sexing the ducklings (and possibly feedback on the phases). I did small back of 4 eggs to ensure that I had the incubator set and proper, and to test the fertility of the ducks. I started with 4 eggs, one was not fertile and sadly one didn't survive hatching.

This is a picture of the 2 ducklings at about 12hrs old. They both look like females to me, but I'm not sure about the one on the left.

While it was sad to loose one I did identify that all 3 of my new fancy digital thermometers are about 1.5 degrees off, and I should have trusted the good old fashion German thermometer.

I've got 21 more WH eggs ready to go in today, along with about 30 White Chantecler.
Thanks in advance for the feedback.

Let me start by saying: Adorable ducklings -and- I'm no help sexing them because I have no idea what to look for.

I'm curious though, is there a way to sex them at hatch? What are you looking for to tell gender?

Edited to add: Nevermind, I Googled it! According to what I found, the right would be a female (light beak ending in dark tip) and I'm assuming the left would be a male (darker beak). Lots of folks mention it wasn't entirely accurate though. So, maybe you could document their growth so we can see what they end up being?!?!Edited by howfunkyisurchicken - 2/28/16 at 12:51pm

Thanks, they are just adorable ducklings, and we just love them as they mature.

The bill sexing is supposed to be 80-90 accurate, so we were hoping to band them and see how accurate it was. The next set of eggs is for 2 different people looking for about half each, and we'd love to send them with an even mix, so that one of them doesn't up all drakes and the other ducks. I'll be doing another 20-30 when these finish for us to keep here.

The duckling on the right would clearly meet the description for a female, but I was unsure on the left. Many of the examples I found for males had a fully dark bill, so I was hoping some others with experience with WH would be able to weigh in when it's a light bill with a dark band.

Thanks for the feedback though, and we'll certainly document the progress for these 2.